Validity and Reliability of the Japanese Version of the Rome III Diagnostic Questionnaire for Irritable Bowel Syndrome and Functional Dyspepsia

BACKGROUND/AIMS: Reliable diagnostic instruments for measuring the presence of functional gastrointestinal disorders based on the Rome III criteria have been lacking in Japan. The aims of the present study were to translate and validate the Rome III diagnostic questionnaire which was widely used in Western countries. METHODS: The original version of Rome III diagnostic questionnaire was translated from English into Japanese through 3 independent forward translations, resolution, back translation and reconciliation of the differences. Forty-nine patients with irritable bowel syndrome (IBS), 32 patients with functional dyspepsia (FD) and 56 subjects without any current GI symptoms as controls were recruited from three hospitals located in different regions of Japan and completed the IBS and FD diagnostic modules twice within 14 days. Kappa statistic was used to assess test-retest reliability. The sensitivity and specificity of each diagnostic module for distinguishing IBS or FD patients from controls was tested. RESULTS: Median kappa statistics were 0.63 for the translated IBS diagnostic module and 0.68 for the FD module. The sensitivity, specificity, and positive predict value of the IBS module against physician diagnosis was 61.2%, 100%, and 100% and those of the FD module was 53.2%, 98.2%, and 94.4%, respectively. Meanwhile, IBS patients were significantly more likely to report blood in stools compared to controls (18.4% vs 1.8%, P < 0.01). CONCLUSIONS: The IBS and FD diagnostic modules on the Japanese version of the Rome III diagnostic questionnaire are valid and reliable. Further studies are warranted to elucidate the diagnostic utility of the red flag questionnaire.

Early Satiety Is the Only Patient-Reported Symptom Associated With Delayed Gastric Emptying, as Assessed by Breath-Test

BACKGROUND/AIMS: To evaluate associations between delayed gastric emptying (GE) assessed by the octanoic acid breath test and upper gastrointestinal (GI) symptoms. METHODS: A historical, prospective study included 111 consecutive symptomatic adults referred for a GE breath test because of upper abdominal symptoms suggestive of delayed GE. Exclusion criteria included underlying organic disease associated with delayed GE. Patients completed a symptom questionnaire and underwent a GE octanoic breath test. Patients with delayed GE were compared with those with normal results, for upper GI symptoms. RESULTS: Early satiety was the only symptom significantly associated with delayed GE. It was observed in 52% of subjects with delayed GE compared to 33% patients with no evidence of delayed GE (P = 0.005). This association was seen for all degrees of severity of delayed GE. Patients with early satiety had a t1/2 of 153.9 +/- 84.6 minutes compared to 110.9 +/- 47.6 minutes in subjects without it (P = 0.002). In a logistic regression model, early satiety was significantly associated with delayed GE (OR, 2.29; 95% CI, 1.01-5.18; P = 0.048). CONCLUSIONS: Early satiety is the only patient-reported GI symptom associated with delayed GE. The utility of GE tests as a clinical diagnostic tool in the work-up of dyspeptic symptoms may be overrated.

Validation of New Symptom-Based Fibromyalgia Criteria for Irritable Bowel Syndrome Co-morbidity Studies

BACKGROUND/AIMS: There is significant co-morbidity between irritable bowel syndrome (IBS) and fibromyalgia syndrome (FMS). However, FMS is diagnosed by physical examination, which limits the conduct of co-morbidity studies in a large population-based study. The purpose of this study was to determine the diagnostic validity of a new symptom-based criteria in patients with FMS and/or IBS using the American College of Rheumatology (ACR) criteria as a gold standard. METHODS: The study participants consisted of women with FMS (n = 30), IBS (n = 27) and controls (n = 28). A new symptom-based diagnostic criteria for FMS comprised a regional pain scale and a visual analogue scale for fatigue. All subjects underwent a physical examination for FMS (ACR criteria) and structured questionnaires of regional pain scale and visual analogue scale for fatigue. A fibromyalgia intensity score was calculated and thresholds of tenderness were determined by a dolorimeter. RESULTS: The number of participants diagnosed with FMS in the entire study population (n = 85) was 31 by the new criteria. Compared to the ACR, the sensitivity of the new criteria was 82.9%, specificity 96.0%, positive predictive value 93.5% and negative predictive value 88.9%. In addition, new criteria were useful for the diagnosis of FMS among the subjects with IBS. A fibromyalgia intensity score was significantly correlated with the threshold of tenderness (r = -0.62, P < 0.001). CONCLUSIONS: The new symptom-based diagnostic criteria for the diagnosis of FMS can be used in large-scale clinical and epidemiological co-morbidity studies, in which physical examination is unfeasible. Gastroenterologists investigating the effects of co-morbid FMS in IBS patients can use these new ciriteria with confidence.

Irritable Bowel Syndrome and Co-morbid Gastrointestinal and Extra-gastrointestinal Functional Syndromes

The irritable bowel syndrome (IBS) is the best known of the functional gastrointestinal tract disorders. Many IBS patients have at least one co-morbid somatic complaint and many meet diagnostic criteria for other functional disorders. Patients with IBS and another functional disorder, in comparison with patients with IBS only, have more severe IBS symptoms, a higher rate of psychopathology, greater impairment of quality of life, and more illness-related work absenteeism. Estimates of the prevalence of IBS in patients with fibromyalgia range from 30-35% to as high as 70%. Studies of IBS among patients with chronic fatigue syndrome have reported a prevalence ranging from 35-92%. The prevalence of IBS among patients with chronic fatigue syndrome is reported to be 14%. IBS patients with other co-morbid functional disorders appear to manifest a greater degree of somatization. It has been suggested that the presence of multiple co-morbid disorders may be a marker for psychological influences on etiology. This raises the question of whether the functional syndromes represent the same pathophysiological process, i.e., are the same entity that has been separated into different clinical entities because of medical sub-specialization, or are indeed separate disorders. While the answer to this question awaits further research, it would appear that most functional patients who meet formal diagnostic criteria for more than one functional disorder manifest one disorder clinically more that the others and seek consultation differentially for that set of symptoms.